Metal complexes of azo dyes and process of production



Patented Feb. 18, 1947 METAL COMPLEXES OF AZO DYES AND PROCESS OF PRODUCTION Harold E. Woodward, Penna Grove. N. J., assignor to E. I. du Pont de Nemours & Company. Wilmington. Del., a corporation of Delaware No Drawing. Application July 13. 1948, Serial No. 494,509

6 Claims.

This invention relates to metallic complexes of azo dyes, being pigments.

Metal compounds or azo dyestuffs, one component of which is anthranilic acid. are known, as shown in Colour Index 216, U. S. Patent 1,783.- 083, and Journal of the Chemical Society, 1938, page 292. None of the compounds so formed have the characteristics of those which I have invented.

It is an object of this invention to produce violet to brown pigments having excellent pigment characteristics.

The object of the invention is accomplished by making monazo colors of the type represented by the formula:

HO CONE-R and metallizing them. In this formula R. and R are aromatic radicals of the benzene or naphthalene series, and the azo and carboxy groups are in ortho position to each other, The azo component and B may bear substituents which do not confer water-solubility, such as alkyl, alkoxy. halogen, and nitro. Among the halogens bromine and chlorine are preferred and among the alkyls, and alkoxys, methyl and methoxy are preferred.

The diazo components of my invention are ortho-amino-benzoic acids which may be substituted by chlorine, bromine, nitro, benzo, allwl, and alkoxy groups. Exemplary thereof are 2- amino-4-bromo-benzoic acid, Z-aminol-methylbenzoic acid, 2-amino-5-methyl-benzoic acid, 2- amino-4-methoxy-benzoic acid, 2-amino-4-nitro-benzoic acid and l-amlno-Z-naphthoic acid. Additional examples are given hereinafter.

The coupling components used in my process are arylamides of Z-hydroxy-Zi-naphthoic acid, in which the amine is from the benzene or naphthalene series. Illustrations oi this class are: 2'-hydroxy-3'-naphthoyl derivatives of oand p-toluidine, o-anisidine, p-brom-aniline, 2-methyl-4- chlor-aniline, 2-chlor-4-methyi-aniline, m-nitroaniline, alpha-naphthylamine and l-amino-t'imethoxy-naphthalene.

In the process of making these pigments it is not necessary to adhere strictly to the conditions given for the diazotizatlon and coupling reaction, but reasonable variations in the concentration, temperature, hydrogen ion concentration and solvent, are allowable as explained in Groggins, Unit Processes in Organic Synthesis, page 145. In the metallization reaction it is desirable to have an acid buffer present in order to assist the reaction of the hydroxyl group. As shown in the examples this buffer may be a basic compound like ammonia or an alkyl amine or a salt of a weak acid. The buffer does not react with the pigment but only with the acid formed in the reaction, and its function is to keep the pH above 5.0. As is usual in the preparation of pigments, the physical form of the pigment may be modifled by making it in solutions oi! different pH. Such different conditions usually affect the masstone oi. the pigment and sometimes afl'ect the tint and also the light fastness.

Cobalt, nickel and copper are elements of atomic numbers 27-29. In general, copper gives the brightest colors and cobalt the dullest. The pigments obtained from the different coupling components are not all equally bright or equally last to light, but they vary from brown to violet and from fair to excellent fastness to light.

The following examples are given for purposes of illustration of the results and principles of the invention but do not constitute a limitation.

Example I A solution of the diazonium carboxylate prepared by treating 137 parts of anthranilic acid with 1.5 equivalents oi. hydrochloric acid and 1 equivalent of sodium nitride was gradually dropped at 10 0. into a solution of 2'75 parts 01' 2'-hydroxy-3'-naphthoyl aniline (Naphthanil AS) and 64 parts of sodium hydroxide in 600 parts of alcohol and 800 parts of water. The red pigment was filtered and washed with 5% brine, then slurried in 10,000 parts of water. To this slurry was added 525 parts oilcopper sulfate crystals and 300 parts of sodium acetate crystals and it was heated to -95 for three hours. After this time the pigment was filtered, washed and dried.

This pigment, when ground in lithographic varnish, gave a maroon ink of very good lastness to light in both the masstone and the undertone (printing tone). When extended with a zinc oxide ink. it gave a red violet tint of Iair tastness to light.

This pigment was incorporated in a water-inlacquer emulsion in which the lacquer phase contained a pigment binding agent. Cotton was printed with this pigmented vehicle. After the violet print was dried at C. for 5 minutes. it showed good fastness to chlorine, power laundering, trubenizing and light, being equal in these gnome tests to violet prints obtained from more e!- pensive types oi pigments.

when 800 parts of ammonium hydroxide solution or 200 parts of diethanolamins was used in place of 300 parts of sodium acetate in the metallization reaction described above, the same pigment was obtained.

This pigment may be represented by the formula lime...

in which R is a radical of the group consisting of phenyl, naphthyl, the nuclearly mono-substituted chloro, bromo, nitro, methyl and methoxy derivatives of phenyl and the derivatives oi phenyl nuclearly di-substituted by chioro and methyl; and R is the nuclear radical of one oi the group consisting oi 1-amino-2- and -2-amino-3-naphthoic acid, z-amino-benzoic acid, and the nuciearly mono-substituted chloro. bromo, nitro, methyl and methoxy derivatives of il-amino-benmic acid; and M is an element of the group con- Ex. Diem component r-h om s-m ouio l mm salt Color 2 Antlmmllio acid p-Chlor-anliine Copper sects Dull violet. 3 ..do Nickel acetate Dark Wu. 4. .do

o-Toluidine Nickel ammonium chloride... Red brown. is, ..do Beta-uaphthylamine. Copger ammonium chloride.-. Maroon. 6. mlno-i-ohlorobenmio acid Aniiine............-.. o Bordeaux 7 2-amino-6-chlorobenmlo acid-. .....do Cobalt ammonium chloride... Gray. 8 .....do... Nickeiammoniumchloride... Brown. 0 2-an1ino-5-chl0robenzolcacid .....do.. ..-..do Brown violet 10.. .....do..-. .....do..-. Co peraoetate Red-violet ii ..do. p-Chicr-anilins o tammonium chloride... Gray. 12 ..do -.do.... Nickelammonlum chloride--. Maroon 1:! .do .....do..- Copper acetate Do. 14 2-amino-rrnitrobenmic aci Aniline. Copper ammonium sulfate. Do. it zamino-a-naphtholc acid" ..-..do... Copper acetate Dull violet 1o .-do -do..- Nickel ammonium chloride--. Maroon.

Example XVII A portion of the pigment of Example 9 was dispersed in water by grinding in a solution of 1,l'-dinaphthyl methane 2,2'-disuli'onic acid, and this dispersion was used for dyeing a piece sisting of copper, nickel and cobalt; the group 01 nylon cloth. The piece was dyed a red color of good fastness to light. In a similar manner M0 the pigment of Example 10 gave on nylon a red violet dyeing of good fastncss to light.

Likewise other pigments of this type were made 5 N and dyed on nylon as shown in the following table.

Ex. Dino component i'ib 'fg Metaisait Color i bio id... Aniii i Az t u nl i iimc lt i ffiwfi p-Anl s i dlne... a e-red. 20 ..do o Coppereoeiate Blul -red.

314M918 xx! in which R is a radical of the group consisting of A water dispersion of the pigment of Example 10, made as in Example 17, was used for beater dyeing of paper. The paper was a red-violet color of good iastness to acid, alkali. ink eradicator and light. Likewise, paper was dyed with the pigment of Example 8, and a red-brown paper oi good i'astness properties was obtained. When the pigment of Example 15 was used in a similar manner, a violet paper was obtained which did not become duller in artificial light.

As many apparently widely diirerent embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that I do not limit myself to the specific embodiments thereof except as defined in the appended claims.

I claim:

phenyl, naphthyl, the nucleariy mono-substituted chloro, brorno, nitro, methyl and methoxy derivatives oi phenyl and the derivatives of phenyl nuciearly di-substituted by chloro and methyl; and M is an element of the group consisting of copper, nickel and cobalt.

3. The pigment represented by the formula 0 i o N 76 4. The copper complex of the menace com- 5 pound which results irom coupling diazotized 2- amino-4-chloro-benzoic acid with the anilide of 2-hydroxy-3-naphthoic acid, and reacting the resulting monazo compound in a solutionot a water-soluble salt of copper, until a metal complex of said monazo compound is produced.

5. The copper com lex of the monazo compound which results I om coupling diazotized 2- aminO-S-naphthoic acid with the anilide of 2- hydroxy-3-naphthoic acid, and reacting the resulting monazo compound in a solution of a weter-soluble salt of copper, until a metal complex of said monazo compound is produced.

6. The process of making a metellized complex which comprises forming a. monazo compound by coupling a diazctized ortho-carboxy-primaryarylamine which is devoid of any other watersolubilizing group, and a 2'-hydroxy-3-naphthoyl arylamide which is devoid oi water-solubilizing groups; and reacting the resulting monazo compound in a solution or a water-soluble salt of an element of the group consisting of copper, nickel and cobalt, until a metal complex of said monazo compound is produced, the aryl radical of said diazotized arylamine being the nuclear radical of one of the group consisting of l-amino- 2- and 2-amino-3-naphtholc acid, Z-amino-ben- 6 zoic acid and the nucleariy mono-substituted chloro, bromo, nitro, methyl and methoxy derivatives of Z-amino-benzoic acid; and said aryl amide group being represented by the formula COHNR wherein R is a radical of the group consisting of phenyi, naphthyl, the nuciearly mono-substituted chloro, bromo, nitro, methyl and methoxy derivatives 01 phenyl and the derivatives, of phenyl nuclearly di-substituted by chlore and methyl.

HAROLD E. WOODWARD.

REFERENCES CITED The following references are of record in the 15 file of this patent:

UNITED STATES PATENTS Number Name Date 1,914,427 Heyna June 30, 1933 2,019,914 Kracker Nov. 5, 1035 1,785,846 Thiess Dec, 23, 1930 FOREIGN PATENTS Number Country Date 48,925 French June 21, 1938 510,479 German Oct. 23, 1930 794,817 French Dec. 26, 1935 Certificate of Correction Patent No. 2,416,248.

February 18, 1947.

HAROLD E. WOODWARD It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 2, line 31, Example 1, for

nitride read nitrite; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Signed and sealed this 22nd day of April, A. D. 1947.

LESLIE FRAZER,

First Assistant Commissioner of Patents.

5 pound which results irom coupling diazotized 2- amino-4-chloro-benzoic acid with the anilide of 2-hydroxy-3-naphthoic acid, and reacting the resulting monazo compound in a solutionot a water-soluble salt of copper, until a metal complex of said monazo compound is produced.

5. The copper com lex of the monazo compound which results I om coupling diazotized 2- aminO-S-naphthoic acid with the anilide of 2- hydroxy-3-naphthoic acid, and reacting the resulting monazo compound in a solution of a weter-soluble salt of copper, until a metal complex of said monazo compound is produced.

6. The process of making a metellized complex which comprises forming a. monazo compound by coupling a diazctized ortho-carboxy-primaryarylamine which is devoid of any other watersolubilizing group, and a 2'-hydroxy-3-naphthoyl arylamide which is devoid oi water-solubilizing groups; and reacting the resulting monazo compound in a solution or a water-soluble salt of an element of the group consisting of copper, nickel and cobalt, until a metal complex of said monazo compound is produced, the aryl radical of said diazotized arylamine being the nuclear radical of one of the group consisting of l-amino- 2- and 2-amino-3-naphtholc acid, Z-amino-ben- 6 zoic acid and the nucleariy mono-substituted chloro, bromo, nitro, methyl and methoxy derivatives of Z-amino-benzoic acid; and said aryl amide group being represented by the formula COHNR wherein R is a radical of the group consisting of phenyi, naphthyl, the nuciearly mono-substituted chloro, bromo, nitro, methyl and methoxy derivatives 01 phenyl and the derivatives, of phenyl nuclearly di-substituted by chlore and methyl.

HAROLD E. WOODWARD.

REFERENCES CITED The following references are of record in the 15 file of this patent:

UNITED STATES PATENTS Number Name Date 1,914,427 Heyna June 30, 1933 2,019,914 Kracker Nov. 5, 1035 1,785,846 Thiess Dec, 23, 1930 FOREIGN PATENTS Number Country Date 48,925 French June 21, 1938 510,479 German Oct. 23, 1930 794,817 French Dec. 26, 1935 Certificate of Correction Patent No. 2,416,248.

February 18, 1947.

HAROLD E. WOODWARD It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 2, line 31, Example 1, for

nitride read nitrite; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Signed and sealed this 22nd day of April, A. D. 1947.

LESLIE FRAZER,

First Assistant Commissioner of Patents. 

